A number of different constructions of clips or the like for securing workpieces in place upon bath bars or other frameworks have been disclosed in the prior art.
Generally, anodizing operations are similar to other electrolytic processes in that workpieces or parts to be anodized or electrolytically treated, must be secured and suspended in various corrosive baths. For example, in conventional anodizing operations, the workpieces are first suspended in a caustic bath for cleaning their surfaces and conditioning them for the anodizing operation. The workpieces are then suspended in an acid tank employed for anodizing. In the acid tank, electrolytic conditions are developed within the bath commonly by employing the walls of the tank as a cathode and an overhead I-beam for coupling the workpiece as an anode. A framework including bath bars extending downwardly into the tank are connected to the overhead beam and are adapted for supporting the workpieces. The workpieces must of course be in conductive engagement with the overhead beam through the bath bars in order for the process to be carried out.
With the above arrangement and with the workpiece for example being aluminum, a current is then caused to pass through the bath for converting the surface of the workpieces to an aluminum oxide coating. The current employed per square foot of workpiece surface area, the time for the process and selection of coloring agents, etc., are of course well known in the electrolytic art.
In any event, the acid tank employed for the anodizing operation is particularly corrosive to all parts of the supporting framework that are suspended within the bath. These parts of course include any means for securing the workpieces to the bath bars.
In the prior art, it was common to employ C-clamps which were conventionally used for clamping the work pieces against the bath bar and thus suspending them within the bath. Although these clamps worked satisfactorily for the purpose, they were found to be very time consuming.
Other clamping arrangements are disclosed for example in U.S. Pat. No. 3,108,058 issued Oct. 22, 1963 to Mines et al and U.S. Pat. No. 3,013,959 issued to Ventre on Dec. 19, 1961.
In the first noted patent, a relatively complex resilient rocker assembly was employed to form a clamp for mounting workpieces on a bath bar and assuring conductive engagement of the workpieces with the bath bars.
The second patent noted above disclosed the use of angled members formed on the bath bars with wedging members being resiliently urged toward the angled members in order to secure workpieces against the bath bar.
Both of these references provided certain improvements over by both of these patents also exhibited certain shortcomings. For example, they were either secured by bolts to the bath bars or included elements on the bath bars so that they could only function in one position. In addition, the clamping mechanisms provided by both of these patents were also relatively complex, requiring substantial time either for installation or mounting of the workpieces. At the same time, since both combinations included parts which were subject to corrosion within the bath, they also exhibited a relatively limited operating life.
In any event, there has been found to remain a need for an improved clamp or device for securing workpieces to a bath bar in anodizing or other electrolytic operations.